osiu97/ESP32-WijiBoard
1
0
Fork 0
Code Issues 10 Pull Requests Packages Projects Releases Wiki Activity

delete homing. Have to redo

Browse Source
This commit is contained in:
PROFERIS - Mi³osz Stocki
2026-07-06 15:40:15 +02:00
parent ee8a2d97ed
commit f652b741ae
5 changed files with 119 additions and 208 deletions
Download Patch File Download Diff File Expand all files Collapse all files
TODO.md
+1 -1
View File
@@ -1 +1 @@
You didn't finish writing home for web. Analyse it properly as it was quota reached. I can see that there is definitely wron position on map at the start. I do not know what else but you should properly finish homing sequence it was done for mcu already Implement mechanical stall homing
src/main.cpp
+1 -96
View File
@@ -50,20 +50,6 @@
#define DEFAULT_SPEED 600.0f // steps/sec #define DEFAULT_SPEED 600.0f // steps/sec
#define DEFAULT_ACCEL 100.0f // steps/sec² #define DEFAULT_ACCEL 100.0f // steps/sec²
// ─── Homing configuration ─────────────────────────────────────────
// TUNE these after first hardware test.
// SEEK_DIR: +1 = CW (positive steps), -1 = CCW toward stop
// SEEK_STEPS: must exceed maximum arm travel (~240° = 1365 steps)
// OP_OFFSET: steps from the mechanical stop to the operating home
// (derived from original PositionControl.cpp homing offsets)
#define M1_HOME_DIR (-1) // ← TUNE: flip to +1 if M1 moves wrong way
#define M2_HOME_DIR (+1) // ← TUNE: flip to -1 if M2 moves wrong way
#define HOME_SEEK_STEPS 1600 // ← TUNE: > max travel; 1600 ≈ 281° of a rev
#define HOME_SPEED 180.0f // ← TUNE: slow seek to avoid missing steps
#define HOME_ACCEL 50.0f // ← TUNE: gentle accel during seek
#define M1_OP_OFFSET 550 // ← TUNE: steps from M1 stop → operating home
#define M2_OP_OFFSET -530 // ← TUNE: steps from M2 stop → operating home
// ─── BLE UUIDs ──────────────────────────────────────────────────── // ─── BLE UUIDs ────────────────────────────────────────────────────
#define SERVICE_UUID "a0b1c2d3-e4f5-6789-abcd-ef0123456700" #define SERVICE_UUID "a0b1c2d3-e4f5-6789-abcd-ef0123456700"
#define CMD_UUID "a0b1c2d3-e4f5-6789-abcd-ef0123456701" #define CMD_UUID "a0b1c2d3-e4f5-6789-abcd-ef0123456701"
@@ -87,7 +73,6 @@ const unsigned long NOTIFY_INTERVAL_MS = 200;
// ─── Forward declarations ───────────────────────────────────────── // ─── Forward declarations ─────────────────────────────────────────
void parseCommand(const String& cmd); void parseCommand(const String& cmd);
void sendPosition(); void sendPosition();
void runHoming();
// ─── BLE Server Callbacks ───────────────────────────────────────── // ─── BLE Server Callbacks ─────────────────────────────────────────
class ServerCallbacks : public BLEServerCallbacks { class ServerCallbacks : public BLEServerCallbacks {
@@ -145,13 +130,7 @@ void parseCommand(const String& cmd) {
Serial.printf("[CFG] Acceleration → %.0f steps/sec²\n", acc); Serial.printf("[CFG] Acceleration → %.0f steps/sec²\n", acc);
return; return;
} }
// HOME – full stall-seek homing sequence // HOME1
if (cmd == "HOME") {
Serial.println("[HOME] Received HOME command");
runHoming();
return;
}
// HOME1 / HOME2 – manual zero (soft zero, no motion)
if (cmd == "HOME1") { if (cmd == "HOME1") {
stepper1.setCurrentPosition(0); stepper1.setCurrentPosition(0);
Serial.println("[S1] Zeroed"); Serial.println("[S1] Zeroed");
@@ -173,80 +152,6 @@ void parseCommand(const String& cmd) {
Serial.printf("[CMD] Unknown command: '%s'\n", cmd.c_str()); Serial.printf("[CMD] Unknown command: '%s'\n", cmd.c_str());
} }
// ─── Stall-based homing sequence ─────────────────────────────────
/**
* Drives each motor slowly into its mechanical hard stop (the arm
* folds against the motor housing). The 28BYJ-48 stalls harmlessly
* for a fraction of a second at the stop. After both stops are
* found, the arm backs off to the operating home position and both
* step counters are zeroed.
*
* This is a BLOCKING call — BLE is not serviced during homing
* (~15-20 s total). The browser shows "Homing…" until the
* HOMED notify arrives.
*
* Tune M1_HOME_DIR, M2_HOME_DIR, HOME_SEEK_STEPS, and OP_OFFSETs
* after the first hardware test.
*/
void runHoming() {
Serial.println("[HOME] Starting homing sequence…");
// Reduce speed for the seek phase
stepper1.setMaxSpeed(HOME_SPEED);
stepper1.setAcceleration(HOME_ACCEL);
stepper2.setMaxSpeed(HOME_SPEED);
stepper2.setAcceleration(HOME_ACCEL);
// ── Seek M1 to its mechanical stop ───────────────────────────
Serial.println("[HOME] Seeking M1 stop…");
stepper1.move(M1_HOME_DIR * HOME_SEEK_STEPS);
while (stepper1.isRunning()) {
stepper1.run();
stepper2.run(); // keep M2 coils energised during M1 seek
}
stepper1.setCurrentPosition(0);
Serial.println("[HOME] M1 stop found → zeroed");
delay(200); // brief pause before M2 seek
// ── Seek M2 to its mechanical stop ───────────────────────────
Serial.println("[HOME] Seeking M2 stop…");
stepper2.move(M2_HOME_DIR * HOME_SEEK_STEPS);
while (stepper2.isRunning()) {
stepper1.run();
stepper2.run();
}
stepper2.setCurrentPosition(0);
Serial.println("[HOME] M2 stop found → zeroed");
delay(200);
// ── Move to operating home (restore normal speed) ─────────────
stepper1.setMaxSpeed(DEFAULT_SPEED);
stepper1.setAcceleration(DEFAULT_ACCEL);
stepper2.setMaxSpeed(DEFAULT_SPEED);
stepper2.setAcceleration(DEFAULT_ACCEL);
Serial.println("[HOME] Moving to operating home…");
stepper1.moveTo(M1_OP_OFFSET);
stepper2.moveTo(M2_OP_OFFSET);
while (stepper1.isRunning() || stepper2.isRunning()) {
stepper1.run();
stepper2.run();
}
// Declare operating home as the new step zero
stepper1.setCurrentPosition(0);
stepper2.setCurrentPosition(0);
Serial.println("[HOME] Homing complete — at operating home (0, 0)");
// Notify the browser so it can sync its step counters
if (bleConnected && pStatusChar) {
pStatusChar->setValue("HOMED");
pStatusChar->notify();
}
delay(50);
sendPosition(); // immediately follow with P:0,0
}
// ─── Send current positions via BLE NOTIFY ──────────────────────── // ─── Send current positions via BLE NOTIFY ────────────────────────
void sendPosition() { void sendPosition() {
if (!bleConnected || !pStatusChar) return; if (!bleConnected || !pStatusChar) return;
web/js/kinematics.js
+26 -26
View File
@@ -33,11 +33,11 @@
// ── Exact constants from PositionControl.cpp ───────────────────── // ── Exact constants from PositionControl.cpp ─────────────────────
const ARM = { const ARM = {
d: 25.8, // full motor separation (mm) d: 25.8, // full motor separation (mm)
d2: 12.9, // half separation; M1 at (+d2, 0), M2 at (-d2, 0) d2: 12.9, // half separation; M1 at (+d2, 0), M2 at (-d2, 0)
l1: 85.0, // proximal link length (mm) l1: 85.0, // proximal link length (mm)
l2: 110.0, // distal link length (mm) l2: 110.0, // distal link length (mm)
STEPS_PER_REV: 2048, STEPS_PER_REV: 2048,
STEP_ANGLE_DEG: 360 / 2048, // ≈ 0.17578125 °/step STEP_ANGLE_DEG: 360 / 2048, // ≈ 0.17578125 °/step
}; };
@@ -48,16 +48,16 @@ const LIMITS = {
// ── Outer board boundary ─────────────────────────────────────── // ── Outer board boundary ───────────────────────────────────────
// The EE cannot be requested outside this rectangle. // The EE cannot be requested outside this rectangle.
X_MIN: -150, // ← TUNE: left edge of board X_MIN: -150, // ← TUNE: left edge of board
X_MAX: 150, // ← TUNE: right edge of board X_MAX: 150, // ← TUNE: right edge of board
Y_MIN: -30, // ← TUNE: bottom (numbers reach ~44 mm; sign coords go lower) Y_MIN: -30, // ← TUNE: bottom (numbers reach ~44 mm; sign coords go lower)
Y_MAX: 145, // ← TUNE: top (highest letter is ~128 mm) Y_MAX: 145, // ← TUNE: top (highest letter is ~128 mm)
// ── Centre mechanism exclusion box ──────────────────────────── // ── Centre mechanism exclusion box ────────────────────────────
// Rectangular zone centred on (0, 0) where the motor housing sits. // Rectangular zone centred on (0, 0) where the motor housing sits.
// The EE and both elbows must stay outside this area. // The EE and both elbows must stay outside this area.
BOX_HALF_W: 30, // ← TUNE: half-width in X (motors at ±12.9, housing wider) BOX_HALF_W: 30, // ← TUNE: half-width in X (motors at ±12.9, housing wider)
BOX_Y_MIN: -10, // ← TUNE: bottom of housing BOX_Y_MIN: -10, // ← TUNE: bottom of housing
BOX_Y_MAX: 40, // ← TUNE: top of housing BOX_Y_MAX: 40, // ← TUNE: top of housing
// ── Elbow exclusion zone (prevents arm crossing near the box) ─ // ── Elbow exclusion zone (prevents arm crossing near the box) ─
// Each elbow has a separate rectangular exclusion box. // Each elbow has a separate rectangular exclusion box.
@@ -66,7 +66,7 @@ const LIMITS = {
// If ELBOW_BOX_X_INNER is 5, the left elbow's X must be > +5 mm // If ELBOW_BOX_X_INNER is 5, the left elbow's X must be > +5 mm
// (can never cross to the other side of the box mid-point). // (can never cross to the other side of the box mid-point).
ELBOW_BOX_X_INNER: 5, // ← TUNE: inner X margin from centre for each elbow ELBOW_BOX_X_INNER: 5, // ← TUNE: inner X margin from centre for each elbow
ELBOW_BOX_Y_MAX: 50, // ← TUNE: Y below which elbow crossing is forbidden ELBOW_BOX_Y_MAX: 50, // ← TUNE: Y below which elbow crossing is forbidden
}; };
// ── Letter / number position lookup table ──────────────────────── // ── Letter / number position lookup table ────────────────────────
@@ -132,23 +132,23 @@ function solve(x, y) {
// ── Motor 1 (pivot at +d2, 0 = +12.9 mm) ───────────────────── // ── Motor 1 (pivot at +d2, 0 = +12.9 mm) ─────────────────────
// xmd = x - d2 is the X component of (target – M1_pivot). // xmd = x - d2 is the X component of (target – M1_pivot).
const xmd = x - d2; const xmd = x - d2;
const s = Math.sqrt(xmd * xmd + y * y); const s = Math.sqrt(xmd * xmd + y * y);
if (s < 1e-6) return { theta1: 0, theta2: 0, reachable: false }; if (s < 1e-6) return { theta1: 0, theta2: 0, reachable: false };
const cosW1 = (l2 * l2 - s * s - l1 * l1) / (-2 * l1 * s); const cosW1 = (l2 * l2 - s * s - l1 * l1) / (-2 * l1 * s);
if (cosW1 < -1 || cosW1 > 1) return { theta1: 0, theta2: 0, reachable: false }; if (cosW1 < -1 || cosW1 > 1) return { theta1: 0, theta2: 0, reachable: false };
const q = Math.atan2(y, xmd); const q = Math.atan2(y, xmd);
const w1 = Math.acos(cosW1); const w1 = Math.acos(cosW1);
const theta1 = q - w1; const theta1 = q - w1;
// ── Motor 2 (pivot at -d2, 0 = -12.9 mm) ───────────────────── // ── Motor 2 (pivot at -d2, 0 = -12.9 mm) ─────────────────────
// xpd = x + d2 is the X component of (target – M2_pivot). // xpd = x + d2 is the X component of (target – M2_pivot).
const xpd = x + d2; const xpd = x + d2;
const t = Math.sqrt(xpd * xpd + y * y); const t = Math.sqrt(xpd * xpd + y * y);
if (t < 1e-6) return { theta1: 0, theta2: 0, reachable: false }; if (t < 1e-6) return { theta1: 0, theta2: 0, reachable: false };
const cosW2 = (l2 * l2 - t * t - l1 * l1) / (-2 * l1 * t); const cosW2 = (l2 * l2 - t * t - l1 * l1) / (-2 * l1 * t);
if (cosW2 < -1 || cosW2 > 1) return { theta1: 0, theta2: 0, reachable: false }; if (cosW2 < -1 || cosW2 > 1) return { theta1: 0, theta2: 0, reachable: false };
const r = Math.atan2(y, xpd); const r = Math.atan2(y, xpd);
const w2 = Math.acos(cosW2); const w2 = Math.acos(cosW2);
const theta2 = r + w2; const theta2 = r + w2;
return { theta1, theta2, reachable: true }; return { theta1, theta2, reachable: true };
@@ -180,16 +180,16 @@ function forward(theta1, theta2) {
// Elbow 1 — tip of Motor 1 proximal link (motor at +d2) // Elbow 1 — tip of Motor 1 proximal link (motor at +d2)
const e1x = +d2 + l1 * Math.cos(theta1); const e1x = +d2 + l1 * Math.cos(theta1);
const e1y = l1 * Math.sin(theta1); const e1y = l1 * Math.sin(theta1);
// Elbow 2 — tip of Motor 2 proximal link (motor at -d2) // Elbow 2 — tip of Motor 2 proximal link (motor at -d2)
const e2x = -d2 + l1 * Math.cos(theta2); const e2x = -d2 + l1 * Math.cos(theta2);
const e2y = l1 * Math.sin(theta2); const e2y = l1 * Math.sin(theta2);
// End-effector: intersection of the two distal-link circles // End-effector: intersection of the two distal-link circles
// (radius l2, centred on each elbow). Pick the "upward" solution. // (radius l2, centred on each elbow). Pick the "upward" solution.
const dx = e2x - e1x; const dx = e2x - e1x;
const dy = e2y - e1y; const dy = e2y - e1y;
const dist = Math.sqrt(dx * dx + dy * dy); const dist = Math.sqrt(dx * dx + dy * dy);
if (dist < 1e-6 || dist > 2 * l2) { if (dist < 1e-6 || dist > 2 * l2) {
@@ -203,15 +203,15 @@ function forward(theta1, theta2) {
}; };
} }
const a = dist / 2; const a = dist / 2;
const h = Math.sqrt(Math.max(0, l2 * l2 - a * a)); const h = Math.sqrt(Math.max(0, l2 * l2 - a * a));
const mx = (e1x + e2x) / 2; const mx = (e1x + e2x) / 2;
const my = (e1y + e2y) / 2; const my = (e1y + e2y) / 2;
// Two intersection candidates // Two intersection candidates
const px1 = mx + h * ( dy / dist); const px1 = mx + h * (dy / dist);
const py1 = my + h * (-dx / dist); const py1 = my + h * (-dx / dist);
const px2 = mx - h * ( dy / dist); const px2 = mx - h * (dy / dist);
const py2 = my - h * (-dx / dist); const py2 = my - h * (-dx / dist);
// Always pick the candidate with higher Y (EE above the elbow line) // Always pick the candidate with higher Y (EE above the elbow line)
@@ -247,15 +247,15 @@ function armsCrossed(theta1, theta2) {
// Elbow positions (same formula as forward()) // Elbow positions (same formula as forward())
const e1x = +d2 + l1 * Math.cos(theta1); const e1x = +d2 + l1 * Math.cos(theta1);
const e1y = l1 * Math.sin(theta1); const e1y = l1 * Math.sin(theta1);
const e2x = -d2 + l1 * Math.cos(theta2); const e2x = -d2 + l1 * Math.cos(theta2);
const e2y = l1 * Math.sin(theta2); const e2y = l1 * Math.sin(theta2);
// Elbow1 (from M1 on the RIGHT) must not appear far to the LEFT at low height // Elbow1 (from M1 on the RIGHT) must not appear far to the LEFT at low height
// Elbow2 (from M2 on the LEFT) must not appear far to the RIGHT at low height // Elbow2 (from M2 on the LEFT) must not appear far to the RIGHT at low height
// Both conditions together catch the "arms have swapped sides" scenario. // Both conditions together catch the "arms have swapped sides" scenario.
const e1_crossed = e1x < -XI && e1y < YM; // M1's elbow went too far left const e1_crossed = e1x < -XI && e1y < YM; // M1's elbow went too far left
const e2_crossed = e2x > XI && e2y < YM; // M2's elbow went too far right const e2_crossed = e2x > XI && e2y < YM; // M2's elbow went too far right
return e1_crossed || e2_crossed; return e1_crossed || e2_crossed;
} }
@@ -285,7 +285,7 @@ function checkWorkspace(x, y) {
// 2. Centre mechanism exclusion box // 2. Centre mechanism exclusion box
if (x > -L.BOX_HALF_W && x < L.BOX_HALF_W && if (x > -L.BOX_HALF_W && x < L.BOX_HALF_W &&
y > L.BOX_Y_MIN && y < L.BOX_Y_MAX) y > L.BOX_Y_MIN && y < L.BOX_Y_MAX)
return { ok: false, reason: `(${x.toFixed(1)}, ${y.toFixed(1)}) is inside the mechanism housing` }; return { ok: false, reason: `(${x.toFixed(1)}, ${y.toFixed(1)}) is inside the mechanism housing` };
// 3. IK geometric reachability // 3. IK geometric reachability
web/js/sections/stepper-test.js
+2 -85
View File
@@ -47,7 +47,6 @@ const PX_D2 = IK.ARM.d2 * SV.SCALE;
// ── Section state ───────────────────────────────────────────────── // ── Section state ─────────────────────────────────────────────────
let steps1 = 0; let steps1 = 0;
let steps2 = 0; let steps2 = 0;
let isHoming = false; // blocks all controls during homing sequence
let eventCleanup = []; let eventCleanup = [];
// ── SVG element refs ────────────────────────────────────────────── // ── SVG element refs ──────────────────────────────────────────────
@@ -226,58 +225,9 @@ async function zeroMotor(motor) {
} }
// ───────────────────────────────────────────────────────────────── // ─────────────────────────────────────────────────────────────────
// Homing // Manual jog
// ───────────────────────────────────────────────────────────────── // ─────────────────────────────────────────────────────────────────
/** Block / unblock all interactive controls while homing is running. */
function setHomingActive(active) {
isHoming = active;
const root = document.querySelector('.section-page');
if (!root) return;
if (active) {
root.classList.add('homing-active');
} else {
root.classList.remove('homing-active');
}
// Update the button label
const btn = document.getElementById('btn-find-home');
const spin = document.getElementById('home-spinner');
const lbl = document.getElementById('home-label');
if (!btn) return;
btn.disabled = active;
if (spin) spin.style.display = active ? '' : 'none';
if (lbl) lbl.textContent = active ? 'Homing…' : 'Find Home';
}
/** Called when the firmware sends HOMED or when simulating. */
function onHomingComplete() {
steps1 = 0;
steps2 = 0;
setHomingActive(false);
renderArmFromSteps();
UI.log('✓ Homing complete — step counters reset to zero.', 'success');
}
async function startHoming() {
if (isHoming) return;
setHomingActive(true);
UI.log('⧐ Homing started — arm moving to mechanical stops…', 'warn');
if (BLE.isConnected()) {
try {
await BLE.write('HOME');
// onHomingComplete() will be called when HOMED notify arrives
} catch (e) {
UI.log(`BLE error during home: ${e.message}`, 'error');
setHomingActive(false);
}
} else {
// Simulation: instant reset
UI.log('[sim] HOME command sent — simulating instant home', 'info');
setTimeout(onHomingComplete, 600);
}
}
// ───────────────────────────────────────────────────────────────── // ─────────────────────────────────────────────────────────────────
// SVG workspace zones (pre-computed) // SVG workspace zones (pre-computed)
// ───────────────────────────────────────────────────────────────── // ─────────────────────────────────────────────────────────────────
@@ -401,19 +351,7 @@ function buildHTML() {
.quick-steps button { flex:1; min-width:30px; padding:4px 2px; font-size:0.68rem; .quick-steps button { flex:1; min-width:30px; padding:4px 2px; font-size:0.68rem;
border-radius:var(--radius-xs); } border-radius:var(--radius-xs); }
/* Disable all interactive elements during homing */
.homing-active button:not(#btn-find-home),
.homing-active input,
.homing-active #scara-svg {
pointer-events: none;
opacity: 0.4;
}
/* Spinner animation for homing button */
@keyframes spin { to { transform: rotate(360deg); } }
.home-spin { display:inline-block; width:13px; height:13px;
border:2px solid currentColor; border-top-color:transparent;
border-radius:50%; animation:spin 0.7s linear infinite;
vertical-align:middle; margin-right:5px; }
</style> </style>
<div class="section-page fade-in"> <div class="section-page fade-in">
@@ -614,19 +552,6 @@ function buildHTML() {
<span style="font-size:0.72rem;color:var(--text-muted)">Incremental step control — bypasses IK</span> <span style="font-size:0.72rem;color:var(--text-muted)">Incremental step control — bypasses IK</span>
</div> </div>
<!-- Find Home -->
<div style="padding:4px 0 14px;border-bottom:1px solid var(--border);margin-bottom:12px">
<div style="font-size:0.70rem;color:var(--text-muted);margin-bottom:8px;line-height:1.5">
⚠️ Drives each arm slowly into its mechanical stop then backs off to
operating home. Takes ~15–20 s. All controls are locked during homing.
</div>
<button class="btn btn-full" id="btn-find-home"
style="background:rgba(255,152,0,0.12);border:1px solid rgba(255,152,0,0.35);
color:var(--accent-amber);font-weight:700;font-size:0.85rem;padding:10px">
<span class="home-spin" id="home-spinner" style="display:none"></span>
<span id="home-label">⌂ Find Home</span>
</button>
</div>
<div class="jog-compact"> <div class="jog-compact">
<!-- Motor 1 --> <!-- Motor 1 -->
@@ -818,11 +743,6 @@ const StepperTestSection = {
// ── BLE NOTIFY position feedback ────────────────────────────── // ── BLE NOTIFY position feedback ──────────────────────────────
function onBLEStatus(e) { function onBLEStatus(e) {
const msg = e.detail; const msg = e.detail;
if (msg === 'HOMED') {
// Firmware completed homing — sync browser counters
onHomingComplete();
return;
}
if (msg.startsWith('P:')) { if (msg.startsWith('P:')) {
const [s1, s2] = msg.slice(2).split(',').map(Number); const [s1, s2] = msg.slice(2).split(',').map(Number);
steps1 = s1; steps2 = s2; steps1 = s1; steps2 = s2;
@@ -831,9 +751,6 @@ const StepperTestSection = {
} }
document.addEventListener('ble:status', onBLEStatus); document.addEventListener('ble:status', onBLEStatus);
// ── Find Home button ──────────────────────────────────────
document.getElementById('btn-find-home').addEventListener('click', startHoming);
eventCleanup = [ eventCleanup = [
() => BLE.off('connected', updateBadge), () => BLE.off('connected', updateBadge),
() => BLE.off('disconnected', updateBadge), () => BLE.off('disconnected', updateBadge),
wiring_diagram.md
+89
View File
@@ -0,0 +1,89 @@
# WijiBoard Wiring Diagram
This document outlines the hardware connections for the WijiBoard.
## Hardware Components
- **Microcontroller**: Waveshare ESP32-S3-Zero
- **Motors**: 2× 28BYJ-48 (5V Stepper Motors)
- **Motor Drivers**: 2× ULN2003 Driver Boards
- **Power System**:
- 4S LiPo Battery
- XH-M609 Battery Low-Voltage Disconnect Module
- 2× Buck Regulators (step-down converters tuned to 5V)
---
## Power Connections
The system is powered by a 4S LiPo battery. To protect the battery from over-discharge, it is connected to an **XH-M609** module. The output of the XH-M609 is split into two separate **Buck Regulators**, both tuned to output 5V.
1. **Buck Regulator 1 (MCU Power)**: Dedicated to powering the ESP32-S3-Zero.
2. **Buck Regulator 2 (Motor Power)**: Dedicated to powering both ULN2003 driver boards to prevent voltage drops or electrical noise from affecting the MCU.
> [!IMPORTANT]
> **Common Ground**: You MUST connect the Ground (GND) from the ESP32 to the Ground (GND) of the ULN2003 drivers. Even though they have separate 5V power supplies, they need a common ground reference for the GPIO logic signals to work correctly.
| Component | Connection | Destination |
| :--- | :--- | :--- |
| **4S LiPo** | `BAT+` / `BAT-` | XH-M609 `VIN+` / `VIN-` |
| **XH-M609** | `VOUT+` / `VOUT-` | Split to **IN+** and **IN-** on both Buck Regulators |
| **Buck 1 (MCU)** | `OUT+ (5V)` | ESP32-S3-Zero `5V` (used as power input) |
| **Buck 1 (MCU)** | `OUT- (GND)` | ESP32-S3-Zero `GND` |
| **Buck 2 (Motors)**| `OUT+ (5V)` | ULN2003 (M1) `+ / 5V` and ULN2003 (M2) `+ / 5V` |
| **Buck 2 (Motors)**| `OUT- (GND)` | ULN2003 (M1) `- / GND` and ULN2003 (M2) `- / GND` |
| **ESP32-S3-Zero** | `GND` | Tie to the motor ground network (Common Ground) |
---
## Motor 1 (Right Motor) Logic
**Physical Location**: Right side (pivot at +12.9mm)
| ESP32-S3-Zero Pin | ULN2003 (Motor 1) Pin |
| :--- | :--- |
| **GPIO 4** | `IN1` |
| **GPIO 5** | `IN2` |
| **GPIO 6** | `IN3` |
| **GPIO 7** | `IN4` |
---
## Motor 2 (Left Motor) Logic
**Physical Location**: Left side (pivot at -12.9mm)
| ESP32-S3-Zero Pin | ULN2003 (Motor 2) Pin |
| :--- | :--- |
| **GPIO 8** | `IN1` |
| **GPIO 9** | `IN2` |
| **GPIO 10** | `IN3` |
| **GPIO 11** | `IN4` |
---
## Stepper to Driver Connections
Simply plug the white 5-pin JST connectors from the 28BYJ-48 motors into the corresponding white sockets on their respective ULN2003 driver boards. The connector is keyed and only fits one way.
## Schematic Overview
```mermaid
flowchart LR
subgraph Power Delivery
BATT[4S LiPo Battery] -->|14.8V| XHM609[XH-M609 Protector]
XHM609 -->|14.8V| BUCK1[Buck Regulator 1]
XHM609 -->|14.8V| BUCK2[Buck Regulator 2]
end
BUCK1 -->|5V Power| ESP[ESP32-S3-Zero]
BUCK2 -->|5V Power| M1_Driver[ULN2003 M1]
BUCK2 -->|5V Power| M2_Driver[ULN2003 M2]
%% Common Ground
ESP -. Common Ground .- M1_Driver
ESP -. Common Ground .- M2_Driver
%% Logic Signals
ESP -- Pins 4,5,6,7 --> M1_Driver
ESP -- Pins 8,9,10,11 --> M2_Driver
%% Motors
M1_Driver == 5-wire cable ==> M1[Motor 1 - Right]
M2_Driver == 5-wire cable ==> M2[Motor 2 - Left]
```